The invention relates to ambulatory crutches and in particular an improved handgrip, which is attached to the crutch in a unique orientation chosen ergonomically to reduce fatigue and usage injury.
Walking with conventional axillary crutches creates harsh forces on the body. These forces are transferred directly from the foot of the crutch to the wrist and hand. Through the dynamic motion of the crutch gait there are moments when the hands take on the full body weight. The standard axillary crutch has a grip that is in plane and 90 degrees to the axis of the crutch. This causes the hand to be bent between 90 to 110 degrees sharply at the wrist. Stresses are indirectly transferred into the ligaments and nerves within the wrist by means of a vertical and horizontal force.
Thus normal crutch grips place the wrist in a severely extended position, as shown in FIGS. 10a, 11a, and 12a. Along with increasing fatigue, this unnatural position puts the wrist at risk for common injuries such as tendonitis, carpal tunnel syndrome, sprains and strains. The common muscles at risk for sprains and strains are the flexor digitorum profundus, flexor digitorum superficialis and flexor carpi ulnaris. While muscle hyper flexion occurs, direct and indirect force is placed on the carpal ligaments the carpal bones and on key nerves such as the median, radial, and ulnar. In addition the weight and shock bearing of the arm and shoulder are affected by these angles leading to overall body fatigue. Thus crutch users often find themselves in treatment and rehabilitation for injuries caused by the use of the crutches themselves. The common medical term for this type of injury is Crutch Paralysis.
There is a need for a crutch grip that places the wrist in a comfortable, neutral position, by improving the length/tension relationship of the engaged muscles to allow for optimal performance and reduced injury. Such a position would set the tone and foundation for better posture and alignment for those using crutches. Improved posture will not only decrease the potential for wrist pain but also for back and shoulder pain by keeping the whole upper extremity in proper alignment. Also, the improvement in posture will lead to improvements in confidence and efficiency in movement using the crutches. Thus it is the object of this invention to provide for both new crutches and as retrofits for existing crutches a novel handgrip device which achieves a neutral, length/tension optimized wrist position to alleviate crutch related injuries and improve crutch user endurance.